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Ecologia populacional de Solanum erianthum D.Don; Population ecology of Solanum erianthum D. Don

Conforti, Thiago Borges
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 26/07/2006 Português
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O objetivo deste trabalho foi avaliar a ecologia populacional da espécie arbórea Solanum Erianthum D. Don em dois remanescentes de Floresta Estacional Semidecidual e verificar a hipótese de que a mesma possui um comportamento de espécie pioneira e colonizadora no início do processo de sucessão nos ecossistemas. Os dois remanescentes de vegetação nativa escolhidos estão inseridos dentro de um contexto de paisagem fragmentada e antropizada, apresentando diferentes níveis de perturbação. As populações foram levantadas através de uma amostragem adaptativa, indicada para espécies que apresentam padrões agrupados de comportamento espacial. Os mosaicos sucessionais onde as populações foram amostradas foram avaliados através da análise silvigênica de desenvolvimento da arquitetura do ecossistema florestal. As duas populações somam 155 indivíduos, sendo uma com 85 indivíduos e uma densidade moderada e outra de 70 indivíduos e uma alta densidade. As densidades avaliadas para nas duas populações parecem estar relacionadas ao histórico de perturbação dos remanescentes a que pertencem. Os 85 indivíduos do remanescente menos perturbado somam uma área amostral de 13.800 m2 distribuídos por todos os 250 ha, em 20 subpopulações da espécie...

Efeitos do pisoteio humano experimental sobre a vegetação em fragmentos de Floresta Pluvial Tropical Atlântica, São Paulo, Brasil; Experimental human trampling effect on the vegetation in fragments of the Atlantic Rain Forest, São Paulo, Brazil

Siles, Maria Francisca Roncero
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 13/02/2009 Português
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O crescente fluxo de visitantes em áreas naturais, com a conseqüente pressão sobre os recursos naturais, provocou o aumento da preocupação com os impactos negativos gerados. A Ecologia de Recreação estuda os impactos das atividades recreativas nos ambientes visitados, ocupando-se de fornecer resultados que sejam úteis ao manejo desses impactos. Os efeitos do pisoteio humano sobre a vegetação têm despertado particular interesse em diversos ecossistemas do mundo, com publicações concentradas basicamente nas regiões temperadas. No presente trabalho foi realizado um estudo experimental de pisoteio para avaliar a resposta da vegetação em áreas de Floresta Pluvial Tropical Atlântica em três Unidades de Conservação no Estado de São Paulo, Brasil. O desenho experimental foi em blocos randômicos, tendo sido aplicados quatro níveis de intensidade de pisoteio, em uma única estação, com medidas feitas imediatamente antes do impacto e repetidas em vários períodos, de modo a acompanhar a recuperação da vegetação. As variáveis analisadas foram: a cobertura vegetal total, a riqueza de tipos vegetais morfo-funcionais, a cobertura de cada tipo e a quantidade de solo exposto. No geral, confirmando estudos anteriores em outras regiões...

Sustentabilidade: a perda do caráter de mudança estrutural do conceito; Sustainability concept: structural change characteristic loss

Sasahara, Camila
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 09/10/2009 Português
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Este trabalho tem o objetivo de estudar o sentido epistemológico do conceito de sustentabilidade ambiental que compreende a revisão teórica dos paradigmas, cartesiano e econômico, orientadores do desenvolvimento da sociedade moderna, que causam as degradações nos âmbitos ambiental e social; e do histórico ambiental, que expressa as diferentes significações atribuídas ao conceito sustentabilidade, ao longo do tempo, sendo hoje a idéia de desenvolvimento sustentável uma idéia amplamente usada. A partir da percepção dessas distintas concepções, analisam-se as bases teóricas definidas pelas correntes da teoria de Kuznets, a de Solow, as leis de mercado, o ecodesenvolvimento e o ecossocialismo, agrupadas nas duas grandes vertentes: da ecologia radical, de ruptura com esse modelo de desenvolvimento, e da ecologia moderada que propõe mudanças sem afetar a estrutura da sociedade. Estas concepções divergem quanto à configuração da relação estabelecida entre as temáticas que compõe a discussão ambiental: a social e a econômica, que se utilizam idéias como a educação, a interdisciplinaridade, a técnica e o desenvolvimento sustentável, de forma díspar. Tais análises são transpostas à pesquisa científica...

Gorgonians of the South of Portugalbiology, ecology and conservation; Gorgónias do sul de Portugalbiologia, ecologia e conservação

Cúrdia, João Luís da Silva
Fonte: Universidade de Aveiro Publicador: Universidade de Aveiro
Tipo: Tese de Doutorado
Português
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O papel ecológico das gorgónias (Octocorallia: Alcyonacea) nos fundos marinhos rochosos é mundialmente reconhecido. Contudo, a informação acerca da ecologia e biologia das espécies de gorgónias nas zonas temperadas do NE Atlântico é manifestamente escassa, especialmente tendo em consideração as actuais perturbações globais, regionais e locais. Nos fundos rochosos da costa algarvia até aos 30 m, verificouse que várias espécies de gorgónias são abundantes e frequentes, nomeadamente Eunicella labiata, Eunicella gazella, Eunicella verrucosa, Leptogorgia lusitanica e Leptogorgia sarmentosa. As populações de gorgónias são co-dominadas por diferentes espécies que apresentaram elevados índices de associação, indicando reduzidos níveis de competição entre elas. Em todo o caso, a estrutura dos povoamentos diferiu com as condições locais. Todas as espécies evidenciaram padrões de distribuição semelhantes ao longo do gradiente de profundidade, i.e. a abundância aumenta significamente com a profundidade após os 15 m. A profundidades mais baixas (até aos 15 m), a distribuição das gorgónias parece ser condicionada por factores abióticos e pela competição com algas. Com efeito, os padrões de distribuição espacial das espécies de gorgónias na costa algarvia são determinados pela interacção de pressões naturais e antropogénicas (ex. pesca). Ainda que as colónias de maior tamanho não tenham sido restritas a áreas menos pescadas...

Morphology and ecology of Achnanthidium caravelensis (Bacillariophyceae), a new species from Portuguese rivers

NOVAIS, M. H; HLÚBIKOVÁ, D.; MORAIS, M.; HOFFMANN, L.; ECTOR, L.
Fonte: Schweizerbart’sche Verlagsbuchhandlung, Stuttgart, Germany Publicador: Schweizerbart’sche Verlagsbuchhandlung, Stuttgart, Germany
Tipo: Artigo de Revista Científica
Português
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Abstract: A new benthic freshwater diatom species belonging to the genus Achnanthidium Kütz. has been recorded from several watercourses in the North of Portugal. Achnanthidium caravelense Novais et Ector is described as a new species based on light and scanning electron microscopic observations, as well as on its ecological preferences as reconstructed from field observations. The most characteristic morphological features of this species are the different outline of the raphe valve (narrowly elliptic with linear margins) and the rapheless valve (narrowly elliptic to narrowly rhombic with moderately convex margins), the non-protracted broadly rounded apices and the length/width ratio. Furthermore, the areolae of the single row along the mantle are elongated and are more or less widely open, which is a characteristic discernible in girdle view under light microscopy. The species that A. caravelense resembles most is A. eutrophilum (Lange-Bert.) Lange-Bert.; nevertheless it can be distinguished from the latter by the different raphe valve outline, its higher valve length/width ratio and autecology. A. caravelense is common and abundant in soft waters with low to moderate nutrient content in the North of Portugal.

Morphology and ecology of Achnanthidium caravelense (Bacillariophyceae), a new species from Portuguese rivers

NOVAIS, M.H.; HLÚBIKOVÁ, D.; MORAIS, M.; HOFFMANN, L.; ECTOR, L.
Fonte: Lucien Hoffmann Publicador: Lucien Hoffmann
Tipo: Artigo de Revista Científica
Português
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A new benthic freshwater diatom species belonging to the genus Achnanthidium Kütz. has been recorded from several watercourses in the North of Portugal. Achnanthidium caravelense Novais et Ector is described as a new species based on light and scanning electron microscopic observations, as well as on its ecological preferences as reconstructed from field observations. The most characteristic morphological features of this species are the different outline of the raphe valve (narrowly elliptic with linear margins) and the rapheless valve (narrowly elliptic to narrowly rhombic with moderately convex margins), the non-protracted broadly rounded apices and the length/width ratio. Furthermore, the areolae of the single row along the mantle are elongated and are more or less widely open, which is a characteristic discernible in girdle view under light microscopy. The species that A.caravelense resembles most is A. eutrophilum (Lange-Bert.) Lange-Bert.; nevertheless it can be distinguished from the latter by the different raphe valve outline, its higher valve length/width ratio and autecology. A. caravelense is common and abundant in soft waters with low to moderate nutrient content in the North of Portugal.

Leishmaniasis transmission: distribution and coarse-resolution ecology of two vectors and two parasites in Egypt

Samy,Abdallah M.; Campbell,Lindsay P.; Peterson,A. Townsend
Fonte: Sociedade Brasileira de Medicina Tropical - SBMT Publicador: Sociedade Brasileira de Medicina Tropical - SBMT
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2014 Português
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Introduction: In past decades, leishmaniasis burden has been low across Egypt; however, changing environment and land use has placed several parts of the country at risk. As a consequence, leishmaniasis has become a particularly difficult health problem, both for local inhabitants and for multinational military personnel. Methods: To evaluate coarse-resolution aspects of the ecology of leishmaniasis transmission, collection records for sandflies and Leishmania species were obtained from diverse sources. To characterize environmental variation across the country, we used multitemporal Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI) data from the Moderate Resolution Imaging Spectroradiometer (MODIS) for 2005-2011. Ecological niche models were generated using MaxEnt, and results were analyzed using background similarity tests to assess whether associations among vectors and parasites (i.e., niche similarity) can be detected across broad geographic regions. Results: We found niche similarity only between one vector species and its corresponding parasite species (i.e., Phlebotomus papatasi with Leishmania major), suggesting that geographic ranges of zoonotic cutaneous leishmaniasis and its potential vector may overlap...

The Environment and the Microbial Ecology of Human Skin

McBride, Mollie E.; Duncan, W. Christopher; Knox, J. M.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1977 Português
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Microbial flora of the skin of three human population groups representing different natural environments was examined quantitatively and qualitatively to determine whether environmental differences in temperature and humidity can influence the microbial flora of normal skin. Five anatomical skin sites - hands, back, axillae, groin, and feet - were sampled from 10 subjects working in a high-humidity, high-temperature environment, 10 subjects from a low-temperature, high-humidity environment, and 10 subjects working in a moderate-temperature and low-humidity environment. Bacterial populations were significantly larger from the back, axillae, and feet in individuals from the high-temperature and high-humidity environment as compared to the moderate-temperature, low-humidity environment. High humidity and low temperature had no significant effect on total populations, but this group showed a higher frequency of isolation of fungi, and gram-negative bacteria from the back and feet. Although there was an indication that increase in the environmental humidity could result in an increased frequency of isolation of gram-negative bacteria, there was no evidence that an increase in either temperature or humidity altered the relative proportions of gram-negative bacteria in the predominantly gram-positive microbial flora found on normal skin. It was concluded that...

Oxygen Sensitivity of Various Anaerobic Bacteria

Loesche, Walter J.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /11/1969 Português
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Anaerobes differ in their sensitivity to oxygen, as two patterns were recognizable in the organisms included in this study. Strict anaerobes were species incapable of agar surface growth at pO2 levels greater than 0.5%. Species that were found to be strict anaerobes were Treponema macrodentium, Treponema denticola, Treponema oralis n. sp., Clostridium haemolyticum, Selenomonas ruminatium, Butyrivibrio fibrisolvens, Succinivibrio dextrinosolvens, and Lachnospira multiparus. Moderate anaerobes would include those species capable of growth in the presence of oxygen levels as high as 2 to 8%. The moderate anaerobes could be exposed to room atmosphere for 60 to 90 min without appreciable loss of viability. Species considered as moderate anaerobes were Bacteroides fragilis, B. melaninogenicus, B. oralis, Fusobacteria nucleatum, Clostridium novyi type A, and Peptostreptococcus elsdenii. The recognition of at least two general types of anaerobes would seem to have practical import in regard to the primary isolation of anaerobes from source material.

Soil Ecology of Coccidioides immitis at Amerindian Middens in California

Lacy, George H.; Swatek, Frank E.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /02/1974 Português
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Outbreaks of coccidioidomycosis and isolation of Coccidioides immitis have been reported from Amerindian middens. This study was undertaken to determine the most important ecological component(s) for the occurrence of C. immitis at archeological sites. Soils from 10 former Indian villages with no prior history of coccidioidal infection were collected and cultured. The physicochemical properties of the midden soils were compared with nonmidden soils and positive soils. The following theories for the sporadic distribution of the pathogen in the soil of the Lower Sonoran Life Zone were considered: (i) the Larrea tridentata (creosote bush) association, (ii) the preference for saline soils, (iii) isolation near rodent burrows, and (iv) animals as possible agents of dispersal. Results showed that a high percentage of the midden soils contained C. immitis, whereas none of the adjacent, nonmidden soils yielded the fungus. Physicochemical analyses revealed that the dark color and alkaline pH of the midden soils were due to past organic contamination. Repeated isolations were made from soils with low to moderate alkalinity. Alkalinity and sandy texture were consistent features of all soils in this study. However, the lack of any reports of nonsandy infested soils possibly indicates that the sandy texture and alkalinity may be factors in the distribution of this fungus. The organic content...

Mercury Adaptation among Bacteria from a Deep-Sea Hydrothermal Vent

Vetriani, Costantino; Chew, Yein S.; Miller, Susan M.; Yagi, Jane; Coombs, Jonna; Lutz, Richard A.; Barkay, Tamar
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /01/2005 Português
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Since deep-sea hydrothermal vent fluids are enriched with toxic metals, it was hypothesized that (i) the biota in the vicinity of a vent is adapted to life in the presence of toxic metals and (ii) metal toxicity is modulated by the steep physical-chemical gradients that occur when anoxic, hot fluids are mixed with cold oxygenated seawater. We collected bacterial biomass at different distances from a diffuse flow vent at 9°N on the East Pacific Rise and tested these hypotheses by examining the effect of mercuric mercury [Hg(II)] on vent bacteria. Four of six moderate thermophiles, most of which were vent isolates belonging to the genus Alcanivorax, and six of eight mesophiles from the vent plume were resistant to >10 μM Hg(II) and reduced it to elemental mercury [Hg(0)]. However, four psychrophiles that were isolated from a nearby inactive sulfide structure were Hg(II) sensitive. A neighbor-joining tree constructed from the deduced amino acids of a PCR-amplified fragment of merA, the gene encoding the mercuric reductase (MR), showed that sequences obtained from the vent moderate thermophiles formed a unique cluster (bootstrap value, 100) in the MR phylogenetic tree, which expanded the known diversity of this locus. The temperature optimum for Hg(II) reduction by resting cells and MR activity in crude cell extracts of a vent moderate thermophile corresponded to its optimal growth temperature...

The movement ecology and dynamics of plant communities in fragmented landscapes

Damschen, Ellen I.; Brudvig, Lars A.; Haddad, Nick M.; Levey, Douglas J.; Orrock, John L.; Tewksbury, Joshua J.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
Português
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A conceptual model of movement ecology has recently been advanced to explain all movement by considering the interaction of four elements: internal state, motion capacity, navigation capacities, and external factors. We modified this framework to generate predictions for species richness dynamics of fragmented plant communities and tested them in experimental landscapes across a 7-year time series. We found that two external factors, dispersal vectors and habitat features, affected species colonization and recolonization in habitat fragments and their effects varied and depended on motion capacity. Bird-dispersed species richness showed connectivity effects that reached an asymptote over time, but no edge effects, whereas wind-dispersed species richness showed steadily accumulating edge and connectivity effects, with no indication of an asymptote. Unassisted species also showed increasing differences caused by connectivity over time, whereas edges had no effect. Our limited use of proxies for movement ecology (e.g., dispersal mode as a proxy for motion capacity) resulted in moderate predictive power for communities and, in some cases, highlighted the importance of a more complete understanding of movement ecology for predicting how landscape conservation actions affect plant community dynamics.

Ecology of Indigenous Lactic Acid Bacteria along Different Winemaking Processes of Tempranillo Red Wine from La Rioja (Spain)

González-Arenzana, Lucía; Santamaría, Pilar; López, Rosa; Tenorio, Carmen; López-Alfaro, Isabel
Fonte: The Scientific World Journal Publicador: The Scientific World Journal
Tipo: Artigo de Revista Científica
Publicado em 12/03/2012 Português
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Ecology of the lactic acid bacteria (LAB) during alcoholic fermentation (AF) and spontaneous malolactic fermentation (MLF) of Tempranillo wines from four wineries of La Rioja has been studied analyzing the influence of the winemaking method, processing conditions, and geographical origin. Five different LAB species were isolated during AF, while, during MLF, only Oenococcus oeni was detected. Although the clonal diversity of O. oeni strains was moderate, mixed populations were observed, becoming at least one strain with distinct PFGE profile the main responsible for MLF. Neither the winemaking method nor the cellar situation was correlated with the LAB diversity. However, processing conditions influenced the total number of isolates and the percentage of each isolated species and strains. The winemaking method could cause that genotypes found in semicarbonic maceration did not appear in other wineries. Four genotypes of O. oeni were isolated in more than one of the rest wineries. These four together with other dominant strains might be included in a future selection process.

West Nile Virus Ecology in a Tropical Ecosystem in Guatemala

Morales-Betoulle, Maria E.; Komar, Nicholas; Panella, Nicholas A.; Alvarez, Danilo; López, María R.; Betoulle, Jean-Luc; Sosa, Silvia M.; Müller, María L.; Kilpatrick, A. Marm; Lanciotti, Robert S.; Johnson, Barbara W.; Powers, Ann M.; Cordón-Rosales
Fonte: The American Society of Tropical Medicine and Hygiene Publicador: The American Society of Tropical Medicine and Hygiene
Tipo: Artigo de Revista Científica
Publicado em 09/01/2013 Português
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West Nile virus ecology has yet to be rigorously investigated in the Caribbean Basin. We identified a transmission focus in Puerto Barrios, Guatemala, and established systematic monitoring of avian abundance and infection, seroconversions in domestic poultry, and viral infections in mosquitoes. West Nile virus transmission was detected annually between May and October from 2005 to 2008. High temperature and low rainfall enhanced the probability of chicken seroconversions, which occurred in both urban and rural sites. West Nile virus was isolated from Culex quinquefasciatus and to a lesser extent, from Culex mollis/Culex inflictus, but not from the most abundant Culex mosquito, Culex nigripalpus. A calculation that combined avian abundance, seroprevalence, and vertebrate reservoir competence suggested that great-tailed grackle (Quiscalus mexicanus) is the major amplifying host in this ecosystem. West Nile virus transmission reached moderate levels in sentinel chickens during 2007, but less than that observed during outbreaks of human disease attributed to West Nile virus in the United States.

Spatial Ecology of the Critically Endangered Fijian Crested Iguana, Brachylophus vitiensis, in an Extremely Dense Population: Implications for Conservation

Morrison, Suzanne F.; Biciloa, Pita; Harlow, Peter S.; Keogh, J. Scott
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 03/09/2013 Português
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The Critically Endangered Fijian crested iguana, Brachylophus vitiensis, occurs at extreme density at only one location, with estimates of >10,000 iguanas living on the 70 hectare island of Yadua Taba in Fiji. We conducted a mark and recapture study over two wet seasons, investigating the spatial ecology and intraspecific interactions of the strictly arboreal Fijian crested iguana. This species exhibits moderate male-biased sexual size dimorphism, which has been linked in other lizard species to territoriality, aggression and larger male home ranges. We found that male Fijian crested iguanas exhibit high injury levels, indicative of frequent aggressive interactions. We did not find support for larger home range size in adult males relative to adult females, however male and female residents were larger than roaming individuals. Males with established home ranges also had larger femoral pores relative to body size than roaming males. Home range areas were small in comparison to those of other iguana species, and we speculate that the extreme population density impacts considerably on the spatial ecology of this population. There was extensive home range overlap within and between sexes. Intersexual overlap was greater than intrasexual overlap for both sexes...

Colonization Responses and Damage by Chilo partellus (Lepidoptera: Pyralidae) to Four Variably Resistant Cultivars of Maize

Kumar, Harish; Nyangiri, Enock M. O.; Asino, Gershon O.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
Português
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Four maize, Zea mays L., cultivars-Inbred A, Mp704, V-37 and Poza Rica 7832—were evaluated for resistance to leaf feeding, stem feeding, and dead heart by a stem borer, Chilo parlellus (Swinhoe) (Lepidoptera: Pyralidae) in the screenhouse under artificial infestation. The responses of C. parlellus (e.g., oviposition, larval arrest and establishment, feeding, and larval growth and development) were studied in separate experiments. Foliar damage ratings, percentage stem length tunneled, and percentage of plants showing dead heart from borer attack were significantly lower on Mp704, V-37, and Poza Rica 7832 than on the susceptible Inbred A. Of the colonization responses, oviposition by C. parlellus on the plants indicated that ovipositional nonpreference contributed to the resistance of Mp704 and V-37 but not to the resistance of Poza Rica 7832. Arrest of neonate larvae on four maize cultivars indicated that orientation nonpreference contributed to the resistance of Mp704 and Poza Rica 7832 but not to the resistance of V-37. Avery low larval establishment on Mp704 contributed to its high resistance to C. parlellus, whereas response to the cultivars V-37 and Poza Rica 7832 indicated moderate resistance. Results from studies on food ingested and larval growth and development indicated a high level of antibiosis in Mp704 corresponding to its high resistance and a moderate level of antibiosis in V-37 and Poza Rica 7832 corresponding to their moderate resistance to C. parlellus. We conclude that both nonpreference and antibiosis types of resistance mechanisms occur in these culti vars.

Do Pollinators Contribute to Nutritional Health?

Ellis, Alicia M.; Myers, Samuel S.; Ricketts, Taylor H.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Português
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Despite suggestions that animal pollinators are crucial for human nutritional health, no studies have actually tested this claim. Here, we combined data on crop pollination requirements, food nutrient densities, and actual human diets to predict the effects of pollinator losses on the risk of nutrient deficiency. In four developing countries and across five nutrients, we found that 0 to 56% of populations would become newly at risk if pollinators were removed. Increases in risk were most pronounced for vitamin A in populations with moderate levels of total nutrient intake. Overall, the effects of pollinator decline varied widely among populations and nutrients. We conclude that the importance of pollinators to human nutrition depends critically on the composition of local diets, and cannot be reliably predicted from global commodity analyses. We identify conditions under which severe health effects of pollinator loss are most likely to occur.

Histochemical study of the midgut in resistant Anticarsia gemmatalis (Hübner) (Lepidoptera: noctuidae) larvae to nucleopolyhedrovirus AgMNPV, fed with genotypes of soybean resistant to insects.

FALLEIROS, A. M. F.; CRUZ, N. A.; FORGHIERE, L. R.; SILVA, M. R.; GALLO, A. R. L.; SILVA, L. X.; HOFFMANN-CAMPO, C. B.; MOSCARDI, F.; LEVY, S. M.
Fonte: In: LATIN AMERICAN MEETING OF CHEMICAL ECOLOGY, 1., 2010, Colonia de Sacramento. Abstracts? Colonia de Sacramento: Latin American Association of Chemical Ecology, 2010. p. 116. Publicador: In: LATIN AMERICAN MEETING OF CHEMICAL ECOLOGY, 1., 2010, Colonia de Sacramento. Abstracts? Colonia de Sacramento: Latin American Association of Chemical Ecology, 2010. p. 116.
Tipo: Resumo em anais de congresso (ALICE)
Português
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This study aimed verify the chemical composition of the midgut of resistant A. gemmatalis larvae to its nucleopolyhedrovirus, treated with soybean genotypes with different concentrations of rutin and genistin The caterpillars, obtained at the Embrapa/Soja (Londrina-PR-Brazil), were fed with the following genotypes "in natura": BRS257 (control), BR16, Dowling, PI229358, PI227687 and lACIOO. The midguts were collected, fixed and pracessed for detection of acids and neutral polysaccharides (glycogen/PAS), proteins and lipids. The midgut oflarvae fed on genotypes lAC100 and PI227687 showed strongest PASpositivity in columnar cells, as observed in control treatment, indicating the presence of neutral polysaccharides, particularly glycogen; only the genotype PI229358 caused moderate reaction to PAS in the goblet cells. To total proteins technique, the columnar cells showed a weak positive staining with moderate response to treatment with PI227687; the goblet cells were positive to the genotypes PI229358 and lACIOO. There was a positive reaction for lipids in the columnar cells with PI 229358, IAC 100 and PI 227687. No reaction was detected for acid carbohydrates in the epithelial cells of the insects fed with any of the genotypes. We conclude that the rutin and genistin from resistant genotypes alters the chemical composition of the midgut epithelium in resistant A. gemmatalis larvae...

Spatial ecology of the critically endangered Fijian crested iguana, Brachylophus vitiensis, in an extremely dense population: implications for conservation

Morrison, Suzanne F.; Biciloa, Pita; Harlow, Peter S.; Keogh, J. Scott
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica Formato: 9 pages
Português
Relevância na Pesquisa
37.172275%
The Critically Endangered Fijian crested iguana, Brachylophus vitiensis, occurs at extreme density at only one location, with estimates of >10,000 iguanas living on the 70 hectare island of Yadua Taba in Fiji. We conducted a mark and recapture study over two wet seasons, investigating the spatial ecology and intraspecific interactions of the strictly arboreal Fijian crested iguana. This species exhibits moderate male-biased sexual size dimorphism, which has been linked in other lizard species to territoriality, aggression and larger male home ranges. We found that male Fijian crested iguanas exhibit high injury levels, indicative of frequent aggressive interactions. We did not find support for larger home range size in adult males relative to adult females, however male and female residents were larger than roaming individuals. Males with established home ranges also had larger femoral pores relative to body size than roaming males. Home range areas were small in comparison to those of other iguana species, and we speculate that the extreme population density impacts considerably on the spatial ecology of this population. There was extensive home range overlap within and between sexes. Intersexual overlap was greater than intrasexual overlap for both sexes...

Ecology of Vibrio cholerae serogroup 01 in aquatic environments

Borroto,René J.
Fonte: Organización Panamericana de la Salud Publicador: Organización Panamericana de la Salud
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/1997 Português
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The endemic and seasonal nature of cholera depends upon the survival of Vibrio cholerae 01 in a viable but not necessarily culturable state in ecologic niches in aquatic environments during interepidemic periods. To understand the ecology of V. cholerae it is necessary to know which aquatic ecosystems can harbor it and thus contribute to the endemic presence of cholera in Latin America. This article summarizes knowledge about the ecology of V. cholerae 01, specifically, the abiotic and biotic factors that are relevant to the microbe’s survival in aquatic environments. This pathogen finds favorable conditions in waters characterized by moderate salinity, high nutrient content, warm temperature, neutral or slightly alkaline pH, and the presence of aquatic macrophytes, phytoplankton, zooplankton, fish, mollusks, and crusta ceans. These ecologic conditions are typical of estuaries and coastal swamps, and toxigenic V. cholerae 01 is now considered an autochthonous member of the microbial flora of these environments. The microorganism has also shown the ability to colonize freshwater ecosystems in its viable but not necessarily culturable form, if organic or inorganic substrates that favor its survival are available.